Question

check whether 5*7+7*3 is composite number and justify

Answer 1

5×7+7×3
35+21=56
which is a composite number as composite number is a set of number which have common factor other than 1.
so factors of 56 are
1×56
2×28
4×14
7×8
8×7
14×4
28×2
56×1
so factors of 56 are =1,2,4,7,8,14,28,56
hence it is a composite number.



hope this answer helps u.
:)

Answer 2

A composite number has more than 2 factors .Only composite numbers can be expressed in the form of product of two numbers other than 1 and itself .

5*7 + 7*3

= 7( 5 + 3)

= 1 * 7 * ( 5 + 3 )

5*7+7*3 can be expressed as product of other numbers

Therefore , 5*7+7*3 is a composite number